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-rw-r--r--arch/i386/kernel/Makefile1
-rw-r--r--arch/i386/kernel/alternative.c10
-rw-r--r--arch/i386/kernel/cpuid.c6
-rw-r--r--arch/i386/kernel/entry.S36
-rw-r--r--arch/i386/kernel/irq.c6
-rw-r--r--arch/i386/kernel/nmi.c2
-rw-r--r--arch/i386/kernel/stacktrace.c98
-rw-r--r--arch/i386/kernel/traps.c39
8 files changed, 161 insertions, 37 deletions
diff --git a/arch/i386/kernel/Makefile b/arch/i386/kernel/Makefile
index cbc1184e9473..1b452a1665c4 100644
--- a/arch/i386/kernel/Makefile
+++ b/arch/i386/kernel/Makefile
@@ -9,6 +9,7 @@ obj-y := process.o semaphore.o signal.o entry.o traps.o irq.o \
pci-dma.o i386_ksyms.o i387.o bootflag.o \
quirks.o i8237.o topology.o alternative.o i8253.o tsc.o
+obj-$(CONFIG_STACKTRACE) += stacktrace.o
obj-y += cpu/
obj-y += acpi/
obj-$(CONFIG_X86_BIOS_REBOOT) += reboot.o
diff --git a/arch/i386/kernel/alternative.c b/arch/i386/kernel/alternative.c
index 7b421b3a053e..28ab80649764 100644
--- a/arch/i386/kernel/alternative.c
+++ b/arch/i386/kernel/alternative.c
@@ -303,6 +303,16 @@ void alternatives_smp_switch(int smp)
struct smp_alt_module *mod;
unsigned long flags;
+#ifdef CONFIG_LOCKDEP
+ /*
+ * A not yet fixed binutils section handling bug prevents
+ * alternatives-replacement from working reliably, so turn
+ * it off:
+ */
+ printk("lockdep: not fixing up alternatives.\n");
+ return;
+#endif
+
if (no_replacement || smp_alt_once)
return;
BUG_ON(!smp && (num_online_cpus() > 1));
diff --git a/arch/i386/kernel/cpuid.c b/arch/i386/kernel/cpuid.c
index a8d3ecdc3897..fde8bea85cee 100644
--- a/arch/i386/kernel/cpuid.c
+++ b/arch/i386/kernel/cpuid.c
@@ -167,6 +167,7 @@ static int cpuid_class_device_create(int i)
return err;
}
+#ifdef CONFIG_HOTPLUG_CPU
static int cpuid_class_cpu_callback(struct notifier_block *nfb, unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
@@ -186,6 +187,7 @@ static struct notifier_block __cpuinitdata cpuid_class_cpu_notifier =
{
.notifier_call = cpuid_class_cpu_callback,
};
+#endif /* !CONFIG_HOTPLUG_CPU */
static int __init cpuid_init(void)
{
@@ -208,7 +210,7 @@ static int __init cpuid_init(void)
if (err != 0)
goto out_class;
}
- register_cpu_notifier(&cpuid_class_cpu_notifier);
+ register_hotcpu_notifier(&cpuid_class_cpu_notifier);
err = 0;
goto out;
@@ -233,7 +235,7 @@ static void __exit cpuid_exit(void)
class_device_destroy(cpuid_class, MKDEV(CPUID_MAJOR, cpu));
class_destroy(cpuid_class);
unregister_chrdev(CPUID_MAJOR, "cpu/cpuid");
- unregister_cpu_notifier(&cpuid_class_cpu_notifier);
+ unregister_hotcpu_notifier(&cpuid_class_cpu_notifier);
}
module_init(cpuid_init);
diff --git a/arch/i386/kernel/entry.S b/arch/i386/kernel/entry.S
index 787190c45fdb..d9a260f2efb4 100644
--- a/arch/i386/kernel/entry.S
+++ b/arch/i386/kernel/entry.S
@@ -42,6 +42,7 @@
#include <linux/linkage.h>
#include <asm/thread_info.h>
+#include <asm/irqflags.h>
#include <asm/errno.h>
#include <asm/segment.h>
#include <asm/smp.h>
@@ -76,12 +77,21 @@ NT_MASK = 0x00004000
VM_MASK = 0x00020000
#ifdef CONFIG_PREEMPT
-#define preempt_stop cli
+#define preempt_stop cli; TRACE_IRQS_OFF
#else
#define preempt_stop
#define resume_kernel restore_nocheck
#endif
+.macro TRACE_IRQS_IRET
+#ifdef CONFIG_TRACE_IRQFLAGS
+ testl $IF_MASK,EFLAGS(%esp) # interrupts off?
+ jz 1f
+ TRACE_IRQS_ON
+1:
+#endif
+.endm
+
#ifdef CONFIG_VM86
#define resume_userspace_sig check_userspace
#else
@@ -257,6 +267,10 @@ ENTRY(sysenter_entry)
CFI_REGISTER esp, ebp
movl TSS_sysenter_esp0(%esp),%esp
sysenter_past_esp:
+ /*
+ * No need to follow this irqs on/off section: the syscall
+ * disabled irqs and here we enable it straight after entry:
+ */
sti
pushl $(__USER_DS)
CFI_ADJUST_CFA_OFFSET 4
@@ -303,6 +317,7 @@ sysenter_past_esp:
call *sys_call_table(,%eax,4)
movl %eax,EAX(%esp)
cli
+ TRACE_IRQS_OFF
movl TI_flags(%ebp), %ecx
testw $_TIF_ALLWORK_MASK, %cx
jne syscall_exit_work
@@ -310,6 +325,7 @@ sysenter_past_esp:
movl EIP(%esp), %edx
movl OLDESP(%esp), %ecx
xorl %ebp,%ebp
+ TRACE_IRQS_ON
sti
sysexit
CFI_ENDPROC
@@ -339,6 +355,7 @@ syscall_exit:
cli # make sure we don't miss an interrupt
# setting need_resched or sigpending
# between sampling and the iret
+ TRACE_IRQS_OFF
movl TI_flags(%ebp), %ecx
testw $_TIF_ALLWORK_MASK, %cx # current->work
jne syscall_exit_work
@@ -355,12 +372,15 @@ restore_all:
CFI_REMEMBER_STATE
je ldt_ss # returning to user-space with LDT SS
restore_nocheck:
+ TRACE_IRQS_IRET
+restore_nocheck_notrace:
RESTORE_REGS
addl $4, %esp
CFI_ADJUST_CFA_OFFSET -4
1: iret
.section .fixup,"ax"
iret_exc:
+ TRACE_IRQS_ON
sti
pushl $0 # no error code
pushl $do_iret_error
@@ -386,11 +406,13 @@ ldt_ss:
subl $8, %esp # reserve space for switch16 pointer
CFI_ADJUST_CFA_OFFSET 8
cli
+ TRACE_IRQS_OFF
movl %esp, %eax
/* Set up the 16bit stack frame with switch32 pointer on top,
* and a switch16 pointer on top of the current frame. */
call setup_x86_bogus_stack
CFI_ADJUST_CFA_OFFSET -8 # frame has moved
+ TRACE_IRQS_IRET
RESTORE_REGS
lss 20+4(%esp), %esp # switch to 16bit stack
1: iret
@@ -411,6 +433,7 @@ work_resched:
cli # make sure we don't miss an interrupt
# setting need_resched or sigpending
# between sampling and the iret
+ TRACE_IRQS_OFF
movl TI_flags(%ebp), %ecx
andl $_TIF_WORK_MASK, %ecx # is there any work to be done other
# than syscall tracing?
@@ -462,6 +485,7 @@ syscall_trace_entry:
syscall_exit_work:
testb $(_TIF_SYSCALL_TRACE|_TIF_SYSCALL_AUDIT|_TIF_SINGLESTEP), %cl
jz work_pending
+ TRACE_IRQS_ON
sti # could let do_syscall_trace() call
# schedule() instead
movl %esp, %eax
@@ -535,9 +559,14 @@ ENTRY(irq_entries_start)
vector=vector+1
.endr
+/*
+ * the CPU automatically disables interrupts when executing an IRQ vector,
+ * so IRQ-flags tracing has to follow that:
+ */
ALIGN
common_interrupt:
SAVE_ALL
+ TRACE_IRQS_OFF
movl %esp,%eax
call do_IRQ
jmp ret_from_intr
@@ -549,9 +578,10 @@ ENTRY(name) \
pushl $~(nr); \
CFI_ADJUST_CFA_OFFSET 4; \
SAVE_ALL; \
+ TRACE_IRQS_OFF \
movl %esp,%eax; \
call smp_/**/name; \
- jmp ret_from_intr; \
+ jmp ret_from_intr; \
CFI_ENDPROC
/* The include is where all of the SMP etc. interrupts come from */
@@ -726,7 +756,7 @@ nmi_stack_correct:
xorl %edx,%edx # zero error code
movl %esp,%eax # pt_regs pointer
call do_nmi
- jmp restore_all
+ jmp restore_nocheck_notrace
CFI_ENDPROC
nmi_stack_fixup:
diff --git a/arch/i386/kernel/irq.c b/arch/i386/kernel/irq.c
index 16b491703967..6cb529f60dcc 100644
--- a/arch/i386/kernel/irq.c
+++ b/arch/i386/kernel/irq.c
@@ -166,7 +166,7 @@ void irq_ctx_init(int cpu)
irqctx->tinfo.task = NULL;
irqctx->tinfo.exec_domain = NULL;
irqctx->tinfo.cpu = cpu;
- irqctx->tinfo.preempt_count = SOFTIRQ_OFFSET;
+ irqctx->tinfo.preempt_count = 0;
irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
softirq_ctx[cpu] = irqctx;
@@ -211,6 +211,10 @@ asmlinkage void do_softirq(void)
: "0"(isp)
: "memory", "cc", "edx", "ecx", "eax"
);
+ /*
+ * Shouldnt happen, we returned above if in_interrupt():
+ */
+ WARN_ON_ONCE(softirq_count());
}
local_irq_restore(flags);
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index a76e93146585..2dd928a84645 100644
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -107,7 +107,7 @@ int nmi_active;
static __init void nmi_cpu_busy(void *data)
{
volatile int *endflag = data;
- local_irq_enable();
+ local_irq_enable_in_hardirq();
/* Intentionally don't use cpu_relax here. This is
to make sure that the performance counter really ticks,
even if there is a simulator or similar that catches the
diff --git a/arch/i386/kernel/stacktrace.c b/arch/i386/kernel/stacktrace.c
new file mode 100644
index 000000000000..e62a037ab399
--- /dev/null
+++ b/arch/i386/kernel/stacktrace.c
@@ -0,0 +1,98 @@
+/*
+ * arch/i386/kernel/stacktrace.c
+ *
+ * Stack trace management functions
+ *
+ * Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
+ */
+#include <linux/sched.h>
+#include <linux/stacktrace.h>
+
+static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
+{
+ return p > (void *)tinfo &&
+ p < (void *)tinfo + THREAD_SIZE - 3;
+}
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer:
+ */
+static inline unsigned long
+save_context_stack(struct stack_trace *trace, unsigned int skip,
+ struct thread_info *tinfo, unsigned long *stack,
+ unsigned long ebp)
+{
+ unsigned long addr;
+
+#ifdef CONFIG_FRAME_POINTER
+ while (valid_stack_ptr(tinfo, (void *)ebp)) {
+ addr = *(unsigned long *)(ebp + 4);
+ if (!skip)
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ skip--;
+ if (trace->nr_entries >= trace->max_entries)
+ break;
+ /*
+ * break out of recursive entries (such as
+ * end_of_stack_stop_unwind_function):
+ */
+ if (ebp == *(unsigned long *)ebp)
+ break;
+
+ ebp = *(unsigned long *)ebp;
+ }
+#else
+ while (valid_stack_ptr(tinfo, stack)) {
+ addr = *stack++;
+ if (__kernel_text_address(addr)) {
+ if (!skip)
+ trace->entries[trace->nr_entries++] = addr;
+ else
+ skip--;
+ if (trace->nr_entries >= trace->max_entries)
+ break;
+ }
+ }
+#endif
+
+ return ebp;
+}
+
+/*
+ * Save stack-backtrace addresses into a stack_trace buffer.
+ * If all_contexts is set, all contexts (hardirq, softirq and process)
+ * are saved. If not set then only the current context is saved.
+ */
+void save_stack_trace(struct stack_trace *trace,
+ struct task_struct *task, int all_contexts,
+ unsigned int skip)
+{
+ unsigned long ebp;
+ unsigned long *stack = &ebp;
+
+ WARN_ON(trace->nr_entries || !trace->max_entries);
+
+ if (!task || task == current) {
+ /* Grab ebp right from our regs: */
+ asm ("movl %%ebp, %0" : "=r" (ebp));
+ } else {
+ /* ebp is the last reg pushed by switch_to(): */
+ ebp = *(unsigned long *) task->thread.esp;
+ }
+
+ while (1) {
+ struct thread_info *context = (struct thread_info *)
+ ((unsigned long)stack & (~(THREAD_SIZE - 1)));
+
+ ebp = save_context_stack(trace, skip, context, stack, ebp);
+ stack = (unsigned long *)context->previous_esp;
+ if (!all_contexts || !stack ||
+ trace->nr_entries >= trace->max_entries)
+ break;
+ trace->entries[trace->nr_entries++] = ULONG_MAX;
+ if (trace->nr_entries >= trace->max_entries)
+ break;
+ }
+}
+
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index e8c6086b2aa1..2bf8b55b91f8 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -115,28 +115,13 @@ static inline int valid_stack_ptr(struct thread_info *tinfo, void *p)
}
/*
- * Print CONFIG_STACK_BACKTRACE_COLS address/symbol entries per line.
+ * Print one address/symbol entries per line.
*/
-static inline int print_addr_and_symbol(unsigned long addr, char *log_lvl,
- int printed)
+static inline void print_addr_and_symbol(unsigned long addr, char *log_lvl)
{
- if (!printed)
- printk(log_lvl);
-
-#if CONFIG_STACK_BACKTRACE_COLS == 1
printk(" [<%08lx>] ", addr);
-#else
- printk(" <%08lx> ", addr);
-#endif
- print_symbol("%s", addr);
- printed = (printed + 1) % CONFIG_STACK_BACKTRACE_COLS;
- if (printed)
- printk(" ");
- else
- printk("\n");
-
- return printed;
+ print_symbol("%s\n", addr);
}
static inline unsigned long print_context_stack(struct thread_info *tinfo,
@@ -144,12 +129,11 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
char *log_lvl)
{
unsigned long addr;
- int printed = 0; /* nr of entries already printed on current line */
#ifdef CONFIG_FRAME_POINTER
while (valid_stack_ptr(tinfo, (void *)ebp)) {
addr = *(unsigned long *)(ebp + 4);
- printed = print_addr_and_symbol(addr, log_lvl, printed);
+ print_addr_and_symbol(addr, log_lvl);
/*
* break out of recursive entries (such as
* end_of_stack_stop_unwind_function):
@@ -162,28 +146,23 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
while (valid_stack_ptr(tinfo, stack)) {
addr = *stack++;
if (__kernel_text_address(addr))
- printed = print_addr_and_symbol(addr, log_lvl, printed);
+ print_addr_and_symbol(addr, log_lvl);
}
#endif
- if (printed)
- printk("\n");
-
return ebp;
}
-static asmlinkage int show_trace_unwind(struct unwind_frame_info *info, void *log_lvl)
+static asmlinkage int
+show_trace_unwind(struct unwind_frame_info *info, void *log_lvl)
{
int n = 0;
- int printed = 0; /* nr of entries already printed on current line */
while (unwind(info) == 0 && UNW_PC(info)) {
- ++n;
- printed = print_addr_and_symbol(UNW_PC(info), log_lvl, printed);
+ n++;
+ print_addr_and_symbol(UNW_PC(info), log_lvl);
if (arch_unw_user_mode(info))
break;
}
- if (printed)
- printk("\n");
return n;
}
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